This invention relates to copying and duplicating devices, and more particularly, to such devices wherein recording is accomplished by means of a noncontact jet drop print head. A number of such devices are shown in the prior art as shown, for instance, by Ranger et al, U.S. Pat. No. 1,817,098, Behane et al, U.S. Pat. No. 3,604,846, and Loughren, U.S. Pat. No. Re. 27,555. Each of these prior art devices supports a copy sheet on a rotating drum, across which a jet drop print head is translated. A somewhat different arrangement is disclosed in Taylor, U.S. Pat. No. 3,564,120, where a plurality of jet drop print heads are scanned in rotary arcs over a print receiving paper being transported in a horizontal plane. These prior art devices are so configured that they are generally adaptable for use in an office copying or duplicating environment. However, they are all considered to be too slow for most office copying requirements.
A faster copier is disclosed in Cahill et al, U.S. Pat. No. 3,689,693, which uses a plurality of jet drop print heads, typically eight, to cooperatively print portions of an original and collectively print an entire reproduction of an original document. This reduces the printing time significantly, but the system is somewhat limited by the fact that it has only one printing nozzle per head. An even faster printer is disclosed by Van Hook, U.S. Pat. No. 4,009,332, which employs multiple nozzle heads which print interlaced helical tracks.
However, both of these devices require the attachment of a printing medium such as paper to a rotating drum which then must rotate a desired number of revolutions under a printing head to accomplish the reproduction of an original document. Paper handling systems for loading and unloading paper onto the drum, combined with different speed of rotation requirements for the drum at different stages of processing, renders these rotating drum systems complex and adversely affects the overall reliability of the system. Accordingly, the need exists in the art for a simple and reliable paper handling system capable of providing a single or multiple pass of a printing medium such as copy paper under an ink jet printing head for the reproduction of original documents.